What Causes Lung Cancer | American Lung Association

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What Causes Lung Cancer

Anyone can get lung cancer. Lung cancer occurs when cells in the lung mutate or change. Various factors can cause this mutation to happen. Most often, this change in lung cells happens when people breathe in dangerous, toxic substances. Even if you were exposed to these substances many years ago, you are still at risk for lung cancer. Talk to your doctor if you have been exposed to any of the substances listed below and take steps to reduce your risk and protect your lungs.

Smoking

Smoking is the number one cause of lung cancer. It causes about 90 percent of lung cancer cases. Tobacco smoke contains many chemicals that are known to cause lung cancer. If you still smoke, quitting smoking is the single best thing you can do for your lung health. Learn how to quit smoking.

Smokers are not the only ones affected by cigarette smoke. If you are a former smoker, your risk is decreased, but has not gone away completely—you can still get lung cancer. Nonsmokers also can be affected by smoking. Breathing in secondhand smoke puts you at risk for lung cancer or other illnesses.

Reduce your risk:

  • Don't start smoking
  • Quit smoking if you smoke
  • Avoid secondhand smoke

Learn more about how to stop smoking or how to help a loved one quit.

Radon

Radon exposure is the second-leading cause of lung cancer. Radon is a colorless, odorless radioactive gas that exists naturally in soil. It comes up through the soil and enters buildings through small gaps and cracks. One out of every 15 homes in the U.S. is subject to radon exposure. Exposure to radon combined with cigarette smoking seriously increases your lung cancer risk.

Reduce your risk: Test your home for radon. You can do this with inexpensive, easy-to-use test kits sold at hardware stores.

Hazardous Chemicals

Exposure to certain hazardous chemicals poses a lung cancer risk. Working with materials such as asbestos, uranium, arsenic, cadmium, chromium, nickel and some petroleum products is especially dangerous. If you think you may be breathing in hazardous chemicals at your job, talk to your employer and your doctor to find out to protect yourself.

Reduce your risk: If you are exposed to dust and fumes at work, ask your health and safety advisor how you are being protected.

Particle Pollution

Particle pollution refers to a mix of very tiny solid and liquid particles that are in the air we breathe. Evidence shows that particle pollution—like that coming from that exhaust smoke—increases the risk of lung cancer.

Reduce your risk: Help fight pollution. Work with others in your community to clean up the air you and your family breathe.

Genes

Genetic factors also may play a role in one's chances of developing lung cancer. A family history of lung cancer may mean you are at a higher risk of getting the disease. If others in your family have or ever had lung cancer, it's important to mention this to your doctor.

Knowing and reducing your risk

Take Action

Protecting your lungs is one of the best ways to stay healthy and reduce your risk of lung cancer. Take steps to protect your lungs from lung cancer all of the time.

    Resources
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    Radon

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    Lung Cancer Risk Quiz | Saved By The Scan

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    Join Freedom From Smoking

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    Reviewed and approved by the American Lung Association Scientific and Medical Editorial Review Panel. Last reviewed November 24, 2017.

    Page Last Updated: March 26, 2018

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